The overall objectives of the Neuropathology Core are to support AD research studies by supplying thoroughly evaluated brain and other tissues from Alzheimer's disease (AD) patients and normal control subjects to investigators. The specific aims of the Neuropathology Core will be to a) perform short postmortem interval autopsies of AD and control subjects and distribute brain tissue to investigators of the Alzheimer Disease Research Center (ADRC) and other AD projects b) describe the extent and distribution of neuropathologic abnormalities and provide the diagnoses of autopsied AD and control subjects for participants in the ADRC and other AD projects, c) correlate the neuropsychologic and clinical data with the neuropathologic findings in AD subjects, d) correlate the neuropsychologic and clinical data with the neuropathologic features in control subjects with emphasis on those with early cognitive decline to determine the neuropathologic features of this group, e) provide appropriate family members of autopsied AD and control subjects with a prompt written report of the neuropathologic findings and diagnoses, and f) maintain a brain bank of CSF blood, brain, and other organs stored at - 70 degreesC and fixed brain tissue from autopsied AD and control subjects for investigators in the ADRC and other AD related projects in this and other institutions. Sections from brain regions immediately adjacent to those used for research studies will be evaluated for histopathologic abnormalities to allow for morphologic correlations with specific research parameters. Standard histologic stains and immunohistochemical reactions will be utilized for diagnoses and quantitation of senile plaques and neurofibrillary tangles. In addition, the Core will perform clinico- pathologic correlative studies on brains of autopsied subjects. The Neuropathology Core also will perform diagnostic studies on the autopsied brains from a large cohort of 670 Catholic sisters (Nuns) who are being evaluated prospectively and who have volunteered for brain donation. The Core also supports two other AD Program Project Grants and several R0-1 AD-related grants.